1. Technical Field
The present invention relates to an insertion plug to be connected to an outlet connected to a power source power source by inserting a pair of blades to the outlet, and more particularly, relates to an insertion plug that can be inserted to both a DC power source outlet connected to a commercial use DC power source and an AC power source outlet connected to a commercial use AC power source.
2. Related Art
Because recently internal operations of many appliances are performed by using DC, it has been considered to adopt DC power sources as power sources for domestic power distribution in order to eliminate waste of electrical power consumption by AC electric supply. Because in a pair of power source lines that distribute power from an AC power source, simply a relative AC voltage is generated between the pair of power source lines, there are no polarities between a pair of terminals of an AC power source outlet connected to a commercial use AC power source, and accordingly no matter to which terminal one blade among a pair of blades of the insertion plug is inserted, such a connection never becomes an erroneous connection, and a pair of terminals of a conventional AC power source outlet have the same shape and are arranged in parallel. On the other hand, one of a pair of power source lines that distributes power from a DC power source is at a ground potential, and the other one is at a potential of a DC voltage, the pair of power source lines have polarities, and a pair of terminals of a DC power source outlet are arranged being oriented to be mutually orthogonal so that one does not insert a pair of blades of an insertion plug that have different polarities erroneously.
Because in earlier stages of the spread of DC electric supply, there are both AC electric supplies and DC electric supplies, there are also two types of appliance that operate with either AC power sources or DC power sources. Therefore, as shown in FIG. 7, a complex outlet 100 to which two types of outlet, that is, an AC power source outlet 101 and a DC power source outlet 102 are provided has been proposed in Patent Document 1 so that any appliance can be used. In this complex outlet 100, a power source line connected to an AC power source is connected to the AC power source outlet 101, and a predetermined DC voltage obtained after smoothing and rectification of an AC power source and then performing DC-DC conversion thereon is applied to a pair of terminals of the DC power source outlet 102.